we have some for our PL'd 4.5yr old DD. she wears them as warm leggings under dresses in the fall & winter. If you go by the # size they are right on. They do their sizing like Hanna Andersson. they are in no way IMO thick enough to use as a cover. I accidentally bought a pair off spots (listed as like new) that were felted they were stiff & not comfortable feeling. If you want to use them at night maybe use a thinner interlock wool cover under them?